Thanks to the previous two posters for trying to help, I am entering the hex key and I did enter it as case sensitive, still can't connect though. I have had this problem since i got the new iPhone, I have just kept my network unsecure. I wanted to secure it though and am still unable to connect my iPhone though. I can't figure out why.
Passwords are case sensitive. Keys are not. Just make sure you're entering the key using the right format.
Are you entering the key like this?
A1:B2:C3:E4:F5
or like this?
A1B2C3E4F5
This last format is the one you should be using. I repeat, this is not case sensitive.
One other question. Are you using a 40 (64) bit key or a 104 (128) bit key. If you're using a 104 bit key, then you should have 26 HEX chars and not 10 .
One final comment. You really, really, REALLY want to use WPA instead of WEP. Trust me, using WEP or no security at all are more or less the same.